Crucible for aluminothermic reactions



Se t.,2, 1930. H. SCHULTZ CRUCIBLE FOR ALUMINOTHERMIC REACTIONS FiledJuly 24, 1929 :NVENTOR BY HIS ATTORNEY Patented Sept. 2, 1930 UNITEDSTATES PATENT mm v HEBMANN SCHULTZ, OF .BERLIN-LANKWITZ, GERMANY,GBU'GIIBLE FOB ALUMINOTHERMIC REACTIONS Application filed lly 24, 1929,Serial No.

like on the one hand, and the all metal or castiron crucible on theother.

The invention is illustrated in the accompanying drawings, in which vFig. 1 is an elevation of .a crucible embodying the invention, and

Rig. 2 is a half section of the same on line 22 of Fig. 1. p

In carrying out alumino-thermic reactions, more particularly ineffecting welds by superheated alumino-thermic steel or iron, two typesof crucibles have been employed, one comprising a shell ofsheet iron orthe like with a thick lining of refractory clay or similar plasticmaterial and the other consisting of a thick walled receptacle of metal,preferably cast iron. Orucibles in which the lining consists entirely ofrefractory clays or the like are open to the objection that they aresubject to rapid erosion due to the action of the slag upon therefractory walls. This difiiculty is obviated by using a crucible madeentirely of thick walls of cast iron which is not attacked by the slagand the surfaces of which, when coated with .slag, are protected fromthe intense heat generated in the molten metal by the alumino-thermicreaction. These cast iron crucibles however are unduly heavy andcumbersome. The present invention is designed to avoid the ob]ectionablefeatures of both of the old types of crucibles and to utilize thesalient advantages of each. To this end, the invention comprises acrucible having a lower section of refractory molded material,preferably en-' closed in a sheet metal casing, and an upper sectionformed of a cast metal-annulus, with suitable connecting means betweenthe sections to form the same into a unitary structure.

Referring to the drawings, a indicates a sheet metal shell or casing,which is provided with a lining b in the form of a thick wall of plasticrefractory material, such as the 880,747, and in Germany August 31,1928.

various clays and compositions used for this purpose, these two elementsconstituting the bottom member or section of the crucible. As indicated,the general shape of the crucible isthat of a frustum of a cone, thelower portion terminating in a pouring gate fitted with the usualrenewable nipple e. Secured to the upper edge of the sheet metal shellor are spaced lugs d I The upper section of the crucible, indicated atc, is formed as a metal annulus, pref- 1 erably of cast iron, shaped toconstitute an extension of the body of the crucible, the lower edge ofthe annulus fitting the upper edge of the refractory lining b and theannulus being provided with lugs d corresponding to the lugs d of thelower section and adapted to receive bolts 7, by means of which thetwosections are locked together.

It will thus be seen that the composite crucible includes alowersection, which will contain practically all of the metal resulting fromthe alumino-thermic reaction, which lower section includes therefractory lining which is not attacked by the molten metal, and anupper metal section with which the slag comes in contact-and which isprotected from the heat of the reaction by the slag, the result being acrucible capable of much more extensive use and with a greatly lessenedtendency toward deterioration and injury because of the fact that therefractory wall of the lower section lies below the body of the moltenslag during the reaction and the metal walls of the upper section areprotected from the superheat of the reaction by the slag.

What I claim is:

1. A crucible for alumino-thermic reactions comprising a lower sectionwith a thick wall of molded refractory material, an upper section ofmetal, and means for connectmg said sections.

2. A crucible for alumino-thermic reactions comprising a lower sectionwith a thick wall of molded refractory material, an upper section ofcast iron, and means for connect ing said sections.

3. A crucible for alumino-thermic reactions comprising a lower sectionwith a thick wall of molded refractory material, a sheet metal shellsurrounding said lower section, v an upper section of metal, and meansfor connectmg the shell to the metal section. 5 4. A crucible foralumino-thermic reactions compnsmga-lower sheet metal shell, a

lining therefor of refracto material, an upper section of cast iron, anlugs on the shell and upper section for securing said elements together.

5. A crucible for alumino-thermic reac-' tions comprising afrusto-conical-sheet metal shell, a lining therefor of refractorymaterial, an upper annular section of cast iron, registering with andforming a continuation of the body of the crucible, and perforated lugson the shell and annular section for connectingthe parts together.

In testimony whereof I aflix my signature.

9-0 HERMANN SCHULTZ.

